Adjustable booster ram assembly for hydraulic motors



L: C.'COLE ADJUSTABLE BOQSTER RAM ASSEMBLY FOR HYDRAULIC MOTORS Filed Dec. 22,4945

u. i F I MMQ Le Oct. 24, 1950 mm on .PatentetFDct. 24, 1950 sms-e9 ADJUSTABLE veoos'rca RAM-ASSEMBLY Fen, HYDRAULIC MOTORS .Lyndon C. Gole,..Cleveland, Qhio, assignor to 7 .H 'P-li L'Development Corporation, Wilmington,

Del. acorporation of Delaware Application December 22, 1 945, .Serial'No. 636,983

1 This invention-relates to fluid operable apparatus and isparti-cularly concerned with u an improved construction for a reciprocating ram having a booster ram.

Rams having booster rams are customarily normed-from solid metal and arbore for the ii-claim. (o1. co -97) booster ram thereafter machined axially within the said ram. The rain is then mounted in a cylinder and the booster ram is secured in the head end of the cylinder and extends into the aforementioned bore of the main ram.

The booster ram is adjustable in the cylinder by being threadedly engaged therewith or threadedly engaging a rotatablemember carried in the cylinder head. In order to effect fluid communication between the working area of the booster ram and the working area of the main ram, it is customary to provide passages in the main ram communicating with the booster ram bore at the proper point. p

The manner of constructing a ram having a booster ram according to the foregoing is expensive because it involves considerable machine work.

The rimary object of the present invention is to provide a construction for a ram having a booster ram which is more economical in both material and labor and produces equivalent or better operation of the motor.

It is another object to provide in combination with a reciprocating ram, a booster ram therefor and means for axiall adjusting the booster ram which is more readily manufactured and assembled than previous types.

Still another object is to provide in combination with a main ram and a booster ram therefor, means for bleeding off air pockets for improving the operation of the apparatus.

These and other objects and advantages will become more apparent upon reference to the accompanying drawing in which:

Figure 1 is a longitudinal section through a booster ram constructed according to this invention;

Figure 2 is a transverse section on the line 22 of Figure 1 showing the fluid passages in the booster ram adjusting screw; and

Figure 3 is a similar view on the line 3--3 of Fig. 1.

Referring to the drawing, N) indicates the cylinder within which is reciprocably mounted a double acting ram 12 which is hollow as at [4 and has an aperture It at the right end thereof which is closed by a plug Is that may be welded or brazed in the said aperture as desired.

The ram 52 is, also aperturedat the leftend as at 20 for receiving a booster ram 22 that comprises a substantially tubular member. The booster ram 22 extends leftwardly from the main ram and passes through a bore 24 in the inwardly projecting boss '28 of the head of the cylinder iii. The extreme left end of the'booster ram 22 is internally threaded for receiving, a screw 28 screw 23 does not project beyond the limits thereof for protecting the-saidscreW from injury.

Suitable packing means asat 34-seal the end cap againstleakage around the *screw, and th'er packing as 'at 36 seals against leakage from between the cylinder and end cap. The screw 28 is shouldered as at 38 to carry the thrust of the booster when the motor is in operation.

In order t prevent rotation of the booster 22 when the screw 23 is rotating to adjust the position of the said booster, there is provided the plate 49 which threads on the left end of said ram and which has a notch therein engaged by a dowel pin 42 that is stationarily mounted in the boss 26.

As a convenient means of supplying fluid to the central passage 44 of the booster ram, the screw 28 comprises the axial grooves 46 down either side thereof which communicate the said central bore with a chamber 41 formed in the left end of the cylinder I0 between the cap 30 and the boss 26.

Fluid is supplied to the chamber 41 and therethrough to the bore 44 by a pipe 58 connected with the cylinder i0. During the time that the ram i2 is moving rightwardly due to pressure supplied to the booster, the right side thereof is exhausted through a conduit 52 while the left side thereof is freely supplied fluid through a conduit 54. When the main ram has moved rightwardly until the transverse bores 56 in the booster communicates with the left-hand side thereof, the conduit 54 is closed by a, check valve (not shown) and the ram l2 thereafter continues movement at reduced speed and increased thrust.

which has a bore therethrough that directs the air into a pocket 54. To bleed off air pockets from the chamber 64 there is provided a pipe 66 that extends into the chamber and leads to the outside of the cylinder l0 through a packing gland, indicated at 61. The pipe 66 may also be used as a gauge line for indicating the pressure acting within the cylinder l0.

According to well known practices the plunger l2 may include piston rings sealing it againstthe cylinder wall, the open end of the cylinder may be closed by suitable packing means, and the bypass port 68 may be provided for halting the advancing travel of the ram at a predetermined point by bypassing the fluid supply thereto.

It will be apparent that a ram and booster ram constructed in this manner has the advantage of being more cheaply built, is more readily adjusted as to the length of the rapid advancing stroke, and has improved means for bleeding 01? air pockets.

It will be understood that this invention is susceptible to modification in order to adopt it to different usages and conditions and, accordingly, it is desired to comprehend such modifications within this invention as may fall within the scope of the appended claim.

I claim:

In a hydraulic motor; a cylinder provided with a main ram-receiving chamber and a separate auxiliary chamber; a hollow ram reciprocable in the main chamber of said cylinder and formed with a first pressure-responsive area and an internal chamber providing a second pressureresponsive area, the internal chamber of said ram being open at one end; a tubular sleeve member formed with an axial bore and having one end communicating with the auxiliary chamber of said cylinder and its opposite end extending within the chamber of said ram, said sleeve member being formed with a screw-threaded opening at one end communicating with the bore of said sleeve and the auxiliary chamber of said cylinder and arranged for sliding movement axially within said cylinder; a screw-threaded member extending through the auxiliary chamber of said cylinder and in threaded engagement with the screw-threaded opening in said sleeve member, said screw-threaded member being formed along its side portions with a longitudinally extending channel providing communication between the auxiliary chamber of said cylinder and the bore of said sleeve member and being rotatable within said cylinder to move said sleeve member axially thereof; and inlet means communicating with the auxiliary chamber of said cylinder for introducing pressure fluid therein. LYNDON C. COLE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,241,691 White Oct. 2, 1917 1,302,246 Trace Apr. 29, 1919 2,346,868 Perry Apr. 18, 1944 2,404,611 Ashbaugh July 23, 1946 2,410,001 Ashbaugh Oct. 29, 1946 

